This project proposes to continue investigations on the molecular organization and metabolism of normal animal and human vitreous. Furthermore, studies are proposed for evaluating the therapeutic value of highly purified hyaluronic acid, a macromolecular component of the vitreous, in certain diseases of the eye. The scope of the project covers the following specific areas of investigation: a) the development of the vitreous with special regard to the formation of collagen fibrils and hyaluronic acid; b) the aging of the vitreous, with special regard to collagen and hyaluronic acid content and to the changes in gel-liquid phases; c) metabolism of hyaluronic acid in the vitreous; d) the Laminar structures in the normal and pathological vitreous; e) vitreous cells; f) the rheology of the vitreous and the structure of glycosaminoglycans of vitreous of mammals and fish; g) the pathology of the vitreous in experimental inflammation; h) the therapeutic effect of hyaluronic acid in the eye; i) the fragmentation of vitreous fibers and membranes.